When it comes to sex among guppies, competition is high for those at the top of the game. To get around this predicament, a recent study has shown, guppies use trickery. Competition in fish of the Poeciliidae…

All organisms have been evolutionary programmed to spread their genes as far and wide as possible. One way to do that is to produce many offspring, and for that animals have developed some very strange…

It turns out guppy genital length is genetic – for females as well as males.
Alice ChaosMay 31, 2013

It’s not always easy to tell if a fish is male or female: they look more or less the same. But there are exceptions, such as guppies and, as with humans, guppy genitalia varies in size across the species…